<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>动画制作</title>
</head>
<body>
    <div class="play-ground">
        <div class="ball"></div>
    </div>
    <style>
        .play-ground{
            width: 600px;
            height: 300px;
            border: 1px solid rgb(176, 71, 71);
            position: relative;
        }
        .ball{
            background-color: rgb(67, 149, 170);
            border-radius: 50%;
            position: absolute;
            animation: ball 7s infinite ease-in-out;
        }

        @keyframes ball{

            from{  
                /*起始start样式，0%亦可写作from*/ 
                width: 50px;
                height: 50px ;
                left: 30px;
                top: 130px;
            }

            24% {
                /*内部第一个关键帧keyframe1样式，24%是根据图示的估计值*/
                width: 225px;
                height: 25px;
                left: 130px;
                top: 20px;
            }

            50% {
                /*keyframe2 样式*/
                width: 100px;
                height: 100px;
                left: 240px;
                top: 100px;
            }

            73% {
                /*keyframe3 样式*/
                width: 100px;
                height: 100px;
                left: 360px;
                top: 200px;
            }

            100% {
                /*end结束样式,100%亦可写作to*/
                width: 150px;
                height: 150px;
                left: 420px;
                top: 70px;
            }

        }
    </style>
</body>
</html>